JPH1120261A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent hooking of a ribbon, breakage of a pin in a print head, and the like, by estimating the returning amount of thickness of a plurality of binding sheets when a touching print head is released in order to correct a set amount and then retracting the print head by a correcting amount thereby setting a gap. SOLUTION: A CPU 31 retrieves a sheet return thickness estimation amount data table stored in the memory 33M of an RAM 33 and determines a sheet return thickness estimation amount corresponding to a detected thickness. A correction set amount is then determined based on a sheet return thickness estimation amount thus determined. A control unit 30 reads out the correction set amount and turns a motor 15 reversely to retract a print head by the correction set amount and then stops the motor 15 thus setting a gap. When such a gap 15 set, hooking of a ribbon, breakage of a pin in a print head, and the like, are prevented and a plurality of binding sheets can be printed smoothly and surely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print head which moves forward until it comes into contact with a plurality of sheets of recording paper, such as a plurality of sheets, supplied to a platen via an ink ribbon. The present invention relates to a printing apparatus for setting a gap by causing the gap to be set.

[0002]

2. Description of the Related Art In FIG. 6, a platen 2 is provided in a main body case (1L, 1R). The carrier 4 on which the print head 5 is mounted is slidably mounted on the shaft 3, and is reciprocated in the X direction by a carrier moving mechanism (not shown) including a carrier motor, a timing belt, a sprocket, and the like.

An ink ribbon drawn from a ribbon cassette (not shown) is interposed between the print head 5 and the recording paper P supplied to the platen 2. Is fed and urged by the ribbon take-up roller.

Here, the gap adjusting mechanism 10 includes an eccentric cam mechanism 11L. 11R, a driven gear 13 and a drive gear 14, a motor (stepping motor) 15, and a motor drive unit 20. Further, the gap setting control means is formed using a part of the function of the control unit 30.

When the motor 15 is rotated forward, the eccentric cam mechanism 11L. The shaft 3 moves forward in a direction approaching the platen 2 by 11R, and retreats in a direction away from the shaft 3 when the shaft 3 is rotated reversely. The movement amount detector 17 for detecting the forward / backward movement is formed of, for example, a slit disk 18 attached to the shaft 3 and an encoder 19.

In a printing apparatus including the gap adjusting mechanism 10 and the gap setting control means (30), when a gap setting command is issued, a driving pulse signal is input from the control unit 30 to the motor driving unit 20, and the motor 15 is driven. Rotate forward. Then, the eccentric cam mechanism 11L, 1
1R operates to advance (forward) the shaft 3, that is, the print head 5, in a direction approaching the platen 2.

Here, the control unit 30 outputs the moving amount detector 17 (1) despite outputting the moving pulse signal.
If the rotation signal of shaft 3 is not output from 9),
It is determined that the print head 5 is not moving. That is, when the stepping motor (15) steps out, it is determined that the print head 5 has contacted the platen 2 at a predetermined pressure. Then, the control unit 30 reads the set amount, and rotates the motor 15 in the reverse direction to retreat (retreat) the print head 5 by the set amount. Then, the motor 15 is stopped. Thus, the gap setting ends.

[0008]

By the way, in the above-described printing apparatus, when the recording paper is a plurality of bound papers, even if the gap is set correctly with respect to the paper thickness, excessive pressing of the ink ribbon from the paper side is performed. When pressure acts, problems such as hooking of the ribbon and breakage of the pins of the print head 5 are likely to occur.

Therefore, in order to prevent such a situation from occurring,
It is conceivable to increase the gap amount. However, in this case, the impact force of the print head 5 is insufficient, resulting in unclear printing.

It is conceivable that the gap can be increased by increasing the operating distance of the head pin. However, this leads to a significant increase in cost and is hardly recognized from the viewpoint of economic efficiency.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a printing apparatus capable of printing a recording sheet such as a plurality of bound sheets smoothly and reliably by preventing ribbon hooking and pin breakage of a print head.

[0012]

SUMMARY OF THE INVENTION The present invention comprises a platen,
A print head, an ink ribbon supplied between the print head and the platen, a gap adjusting mechanism formed so that the print head can be moved forward and backward with respect to the platen to adjust the gap, and one of the gap adjusting mechanism. The print head is rotated until the print head is brought into contact with the recording paper, such as a plurality of sheets, supplied to the platen, and then the print head is moved back by a set amount to set the gap. A printing device provided with a gap setting control unit, wherein a set amount correction unit that corrects the set amount in accordance with an estimated thickness return amount of the plurality of sheets when the contact by the print head is released is provided. The gap setting control means is configured to be able to set a gap by using a correction set amount instead of the set amount.

In this invention, when the recording sheet is a plurality of sheets, the thickness of the sheet is returned after the contact of the print head by the print head is released, and the set amount correcting means adjusts the contact of the print head. The retreat amount (set amount) after contact is corrected,
The print head is moved back by the correction set amount.

Therefore, there is no possibility that an excessive pressing force acts on the ink ribbon from the side of a plurality of spelled sheets due to a shortage of the gap. It is possible to print single-sheet paper.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 to 5, the basic configuration of the printing apparatus is the same as that of the conventional example (FIG. 6). Is set, the set amount is corrected by estimating the amount by which the thickness of the plurality of sheets is returned, and the print head 5 is moved back by the corrected set amount so that the gap can be set.

The same components as those in the conventional example (FIG. 6) are denoted by the same reference numerals, and description thereof will be simplified or omitted.

In FIG. 1, reference numeral 30 denotes a control unit of the printing apparatus, which comprises a CPU 31, a ROM 32, a RAM 33, a keyboard 34, a display 35, a timer 36, an input / output port (I / O) 37 and the like. I / O port 3
7, a motor (stepping motor) 15 of the gap adjusting mechanism 10 is connected via a motor drive unit 20 and an encoder 1 of a movement amount detector (17).
9 is connected.

Here, according to the present invention, when the recording paper is a plurality of bound papers P, as shown in FIGS. 2A and 2B, when the print head 5 comes into contact with a predetermined pressure at the time of gap adjustment, it is compressed. Paying attention to the fact that when the contact is released, the thickness returns and becomes thicker than at the time of contact, and set amount correction means (31, 32) are provided, and printing is performed in consideration of the thickness return (a). The retreat amount (set amount S) of the head 5 is to be corrected.

The set amount correcting means (31, 32) is for setting a plurality of sheets P when the contact by the print head 5 is released.
Is a means for correcting the set amount S according to the estimated thickness return amount. In this embodiment, as shown in FIG.
Is stored in the memory 33 of the RAM 33. The estimated paper return thickness data table TB indicating the correspondence between the thickness (t1) of the plurality of sheets bound at the time of contact and the thickness (t1 ') when the contact is released.
3M.

Next, the operation of this embodiment will be described with reference to the flowchart shown in FIG. When a gap setting command is issued in the printing apparatus, a drive pulse signal is input from the control unit 30 to the motor drive unit 20, the motor 15 rotates forward, and the print head 5 is moved (S
T10).

If the rotation signal of the shaft (3) is not output from the encoder 19 despite the output of the advance pulse signal, the control unit 30
Is determined not to be moving. That is, when the stepping motor (15) steps out, it is determined that the print head 5 has contacted the platen 2 with a predetermined pressure (YE in ST11).
S). From this contact position, the thickness (t
1) is detected (ST12).

The CPU 31 has a memory 33M in the RAM 33.
Is retrieved from the paper return thickness estimation amount data table TB stored in the storage device, and the paper return thickness estimation amount corresponding to the detected thickness (t1) is obtained. Then, a correction set amount (S ') is determined based on the obtained estimated sheet return thickness (ST13).

Then, the control unit 30 reads the correction set amount (S '), and rotates the motor 15 in the reverse direction to move (retreat) the print head 5 by the correction set amount (S') (ST14). . Then, the motor 15 is stopped (S
T15). Thus, the gap setting ends.

By setting the gap in this manner, as shown in FIG. 4, the rotational torque of the ink ribbon can be reduced as compared with the case where no correction is made.

According to this embodiment, however, the set amount correcting means (31, 32) is provided, and when the contact by the print head 5 is released, the amount by which the thickness of the plurality of sheets P is returned (a ) Is estimated to correct the set amount (S), and the gap can be set by retreating the print head 5 by the corrected set amount (S ′). To prevent multiple sheets of paper P
Can be printed.

[0026]

According to the present invention, the set amount correcting means is provided, and the set amount is corrected by estimating the amount by which the thickness of a plurality of sheets is returned when the contact by the print head is released. Since the gap can be set by retracting the print head by the correction set amount, it is possible to print the recording paper such as multiple sheets smoothly and reliably by preventing ribbon hooking and pin breakage of the print head. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of the present invention.

FIG. 2 is a diagram for explaining a phenomenon in which the thickness of a plurality of sheets is returned.

FIG. 3 is a view for explaining a return thickness estimation amount data table of a plurality of sheets bound together;

FIG. 4 is a diagram for comparing a ribbon rotation torque before and after a set amount correction.

FIG. 5 is a flowchart for explaining the operation.

FIG. 6 is a view for explaining a conventional configuration of a printing apparatus having a gap adjusting function.

[Explanation of symbols]

2 Platen 5 Print head 10 Gap adjusting mechanism 31 CPU (set amount correcting means, gap setting control means) 32 ROM (set amount correcting means, gap setting control means)

Claims (1)

[Claims] 1. A gap adjusting mechanism formed so that a gap can be adjusted by moving a print head forward and backward with respect to a platen, and a motor forming a part of the gap adjusting mechanism is operated to rotate the print head to remove the ink ribbon. A gap setting control means for moving the recording head such as a plurality of sewn sheets supplied to the platen through a predetermined pressure until the recording paper abuts at a predetermined pressure, and retreating the print head by a set amount after the abutment to set a gap. A printing device comprising: a set amount correction unit configured to correct the set amount according to an estimated return thickness of the plurality of sheets when the contact by the print head is released; A printing apparatus, wherein the means is configured to be able to set a gap by using a correction set amount instead of the set amount.